A known face shock absorber is disclosed in USSR Inventor's Certificate No. 697,683. The known device consists of a top adapter with a housing screwed up to it. Inside the housing there is disposed a spindle. The bottom end of the spindle ends with a bottom adapter. Inside a chamber enclosed by a top and a bottom disk, the housing and the spindle, there are disposed active elements (rings woven of small steel wires). Above the top disk, there is screwed up a limiting nut. Underneath the active elements are spiral springs. The active elements are supported by an intermediate wall which is part of the housing.
Drawbacks of this known type of shock absorber include:
the ring-shaped active elements woven of small steel wires have a low coefficient of energy conversion and a low serviceability;
there is a high loading of the spiral springs by the acting forces because of the single-section arrangement of the active elements, and this does not allow the use of the shock absorbers for multi-section drilling.
It is, therefore, a general object of this invention to develop a face shock absorber with variable characteristics of the working system in which the active elements have a high coefficient of conversion and a great duration of operation, which ensures the damping of longitudinal vibrations in a wide range.